Skid beam supporting structure for the heating furnace of walking beam type

ABSTRACT

In walking beam equipment consisting of movable skid beams and fixed skid beams for a heating furnace of the walking beam type, a skid beam supporting structure, of which tubular supports and horizontal members are erected to form a shape similar to the letter &#39;&#39;&#39;&#39;H&#39;&#39;&#39;&#39; sectionally, these members being connected so as to have cooling water run internally therethrough, with the cooling water discharging tubes set inside the supports with the openings thereof placed near the tops of the supports.

United States Patent Mori et al.

[4 1 Aug. 29, 1972 [54] SKID BEAM SUPPORTING STRUCTURE FOR THE HEATING FURNACE OF WALKING BEAM TYPE [72] Inventors: Taketoshi Mori, 101 Tsukita-shijo, Yawata-ku, Fukuoka Prefecture, Kitakyushu; Sizuo Iwatalte, 5-22, Wakasono-l-chome, Kokura-ku, Fukuoka Prefecture, Kitakyushu, both of Japan 22 Filed: Nov. 23, 1970 211 Appl.No.: 91,754

[30] Foreign Application Priority Data Nov. 24,1969 Japan ..44/11l226 [52] U.S. Cl. ..263/6 A [51] Int. Cl ..F27d 3/12 [58] Field of Search ..263/6 R, 6 A

[56] References Cited UNITED STATES PATENTS 3,471,134 10/1969 Cone ..263/6A l/l971 Dessarts ..263/6 A 3/1971 Kakuta et al ..263/6 A Primary ExaminerCharles J. Myhre Att0rneyWenderoth, Lind & Ponack 57 ABSTRACT In walking beam equipment consisting of movable skid beams and fixed skid beams for a heating furnace of the walking beam type, a skid beam supporting structure, of which tubular supports and horizontal members are erected to form a shape similar to the letter H sectionally, these members being connected so as to have cooling water run internally therethrough, with the cooling water discharging tubes set inside the supports with the openings thereof placed near the tops of the supports.

4 Claims, 7 Drawing figures Patented Augz s, 1972 3,681,427

- 3 Sheets-Sheet 1 TAKETOSHI MORI and SIZUO IWATAKE I INVIENTORSIQ ATTORNEYS Patented Aug. 29, 1972 3 Sheets-Sheet 2 .VFIG.4

FIG. 5

TAKETOSQHI MORI and SIZUO IWATAKE, v

INVENTOR. s BY/DWIWVM Patented Au 29, 1972. 3,687,427

3 Sheets-Sheet 5 F IG 6 PRIOR ART TAKETOSHI MORI and SIZUO IWATAKE,

INVENTOR. s,

SKID BEAM SUPPORTING STRUCTURE FOR THE HEATING FURNACE OF WALKING BEAM TYPE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates, in general, to an improvement of the skid beam supporting structure for a heating furnace of the walking beam type, and particularly to a skid beam supporting structure with the capa- O bility of improved heating and transporting of the tobe-heated materials of various sizes and also with the effect that heating of such materials is raised to reduce the irregularity thereof to a minimum.

2. Description of the Prior Art The transporting apparatus for a heating furnace of the walking beam type or the like consists, in general, of fixed skid beams and movable skid beams and a driving device for the movable skid beams. The transportation of to-be-heated materials such as steel slabs or billets in the furnace is so carried out that the to-beheated materials are charged onto the first fixed skid beam and are moved forward above the fixed skid beams stepwise by strikes of the parallelograrrrrnic movement of the movable skid beams.

More specifically, a to-be-heated material charged on the first fixed beam is caught by and transferred to a movable skid beam; then the so transferred material is transported by the distance of the forward movement of the movable skid beam, and is transferred onto another fixed skid beam right below the position where the movable skid beam takes a downward movement. As for this movable skid beam, it takes a backward movement to the original position, completing one cycle of the parallelogrammic movement. Through a series of cyclic movements, as mentioned above, to-beheated materials are transported stepwise through the furnace, and heated to the temperature for rolling and other purposes.

All the skid beams are supported at their feet by columnar supports (called supports) which are made of steel pipes. These pipes are cooled by water separately each from other, and are covered by a refractory material to protect against high temperature inside the furnace.

Meanwhile, the operation of a heating furnace of the walking beam type having such movable skid beams as mentioned above, has a difficulty which is found less in the operation of a heating furnace of the so-called pusher type moving forward to-be-heated materials on a fixed hearth (skid) by pushing them from the rear end. That is, because of the structure of the furnace of the former type, both the movable skid beams and the fixed skid beams are greatly affected by forces from the direction of width of the furnace, that is, eccentric load and snaking. Moreover, there are also with the furnace of walking beam type possibilities of thermal deformation of the supports which may have been stripped of the refractory material covering them due to impact at the time of transference of to-be-heated materials from one skid beam to another. Such deformation may cause sideslip of the to-be-heated material while being transported in the furnace, the degree of such sideslip being so accumulated as it is transported, as to have their ends contact or hit the wall of the furnace, damaging it and causing irregularity of ends of the heated materials, which may result in very inefficient and delayed removal of the material from the furnace.

For the prevention of such complications, there has been made and practised an improvement of the above furnace, wherein a pair of supports placed so as to interpose the fixed skid beam between them, are connected tightly at their tops with a horizontal member, which structure is shaped like a hair pin, and is, therefore, called the hair pin type, thereby preventing snaking of the movable skid beams and the resulting deformation thereof.

However, in the case of this improved structure, the position of the horizontal members for the supporting structure of the movable skid beams is very near the bottom of the to-be-heated materials, therefore, these materials are affected by the water cooling of said horizontal members or are prevented from being heated by heat transmitted from the bottom side, thus producing the so-called shadow mark or causing such defects as irregular rolling, and lowering the yield of product. In order to carry out, without trouble, heating and transportation of to-be-heated materials of various sizes, two fixed skid beams on both sides of the to-beheated material are not sufficient for supporting the material, thus requiring one or more fixed skid beams to be installed between the width of the movable skid beam. However, when the movable skid beam moves up to lift the to-be-heated material, the horizontal member of the supporting structure for said movable skid beam will hit the fixed skid beam installed between the movable skid beams. This makes it impracticable to install fixed skid beams between the movable skid beams. Therefore, use of the hair pin type of supporting structure for the movable skid beams has the disadvantage of restricting the size of materials to be heated thereon.

SUMMARY OF THE INVENTION A purpose of the present invention is to provide a skid beam supporting structure capable of improved heating and transporting of to-be-heated materials of various sizes.

Another purpose of the present invention is to provide a skid beam supporting structure with the heat transmitting effect so improved as to prevent production of shadow marks and irregular heating of the tobe-heated materials.

Another purpose of the present invention is to provide a skid beam supporting structure capable of cooling the supports with water regularly, thereby reinforcing the strength of the supports and preventing sideslip of the to-be-heated materials being transported through the heating furnace.

In walking beam equipment consisting of movable skid beams and fixed skid beams, the present invention relates to a skid beam supporting structure, an improvement of which is characterized by being constructed with, as one group of elements, tubular supports each having both upper and lower ends stopped, having an opening for the supply or discharge of cooling water near the lower end and having movable skid beams fixed at their tops. As another group of elements, the structure includes tubular horizontal members each connecting fixedly between a pair of said supports facing each other, at a position of appropriate height so as to have cooling water run through its inside and the inside of the so connected supports; and, as another group of elements, cooling water discharging tubes each running through said supports with the openings placed near the tops of the supports.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a longitudinally sectioned view of a heating furnace of the walking beam type.

FIG. 2 shows the section of the furnace of FIG. 1 along the line II-II as viewed in the direction of the arrow.

FIG. 3 shows the section of the furnace of FIG. 1 along the line HI-III as viewed in the direction of the arrow.

FIG. 4 shows a sectional view of the support as cooled with water according to the present invention.

FIG. 5 shows a sectional view of the support as cooled but not according to the present invention.

FIGS. 6 and 7 show side views of the support of conventional type.

DESCRIPTION OF. THE PREFERRED EMBODIMENT The following is detailed explanation of the present invention using a preferred embodiment shown on drawings:

In the heating furnace 1 shown in FIGS. 1 to 3, 2 indicates the fixed skid beam, and 4 indicates the movable skid beam, these being made of steel pipes so as to be cooled with water. The upper structure for holding to-be-heated materials may be any one of and not limited to those of the rail type, stud type and hot-top type.

As shown in FIG. 1, a to-be-heated steel slab S is placed on the fixed skid beam 2 set on the support 3; the steel slab S is transferred onto the movable skid beam 4 just at the time when the movable skid beam 4 driven by the driving device (not shown on the figure) passes the upper surface line of the fixed skid beam 2 while it takes the upward movement from (a) to (b) When the movable skid beam 4 passes again the upper surface line of the fixed skid beam 2 after its forward movement from (b) to (c) and during its downward movement from (c) to (d), the steel slab S is transferred back onto the fixed skid beam 2. Then, the movable skid beam 4 returns to the original position (a). Series of such link like periodic movement of the movable skid beams makes the steel slab S move in the heating furnace stepwise and at a constant speed when measured wholly over the furnace.

5 indicates the supporting structure for the movable skid beam 4, which is constructed with a pair of supports 6 and 7 facing each other and one horizontal member 8, such construction being shaped like the letter H.

The supports 6 and 7 are tubes with both ends stopped, and have respectively the cooling water introducing opening 9 and the cooling water discharging opening 10 near their lower ends. With these openings 9 and 10 for introducing and discharging cooling water there are connected respectively the water introducing valve 11 and thewater discharging valve 12. Said facing supports 6 and 7 are connected fixedly at a position of appropriate height with said horizontal member 8, so that cooling water introduced through the water introducing valve 11 runs through the support 6, the horizontal member 8 and the support 7, and is discharged through the water discharging valve 12, thereby cooling these members. As mentioned above, the supporting structure 5 is strongly constructed; besides, it is cooled with cooling water, therefore, it will not deform, even though subjected to high temperature, thereby preventing sideslipv of the to-be-heated material S.

One of the important points of the present invention lies in the position where horizontal member 8 is connected with the supports 6 and 7. As mentioned above, in case the tubular horizontal member 8 is connected with the supports 6 and 7 at their upper ends, the effect in transmitting heat to the to-be-heated material S is very low, causing shadow marks and making it impossible to set the fixed skid beam 2' for the heating and transportation, without trouble, of the to-be-heated materials S of various sizes, and thus deteriorating the functions of the furnace. If the connecting position is too low, the supporting force will be lowered, as a matter of course. Also, the connection at such position corresponds with the direction of the flames, as the heating burner 15 is installed on the side wall, thus greatly lowering the heating efficiency in the furnace. 15

In view of the above prior art weak points, the inventors of the present invention have determined that if the horizontal member 8 is fixedly connected to supports 6 and 7 below the tops thereof by an amount of 30 40 percent of the height of said supports 6 and 7 from the floor level, then the horizontal member 8 will not hit the fixed skid beam 2', and the supporting force and heat transmitting effect are greatly improved, thus raising the operation efficiency as a whole.

However,in case the position where the supports 6 and 7 are connected with the horizontal member 8, is set as mentioned above, air stays in the parts A and B, as shown in FIG. 5, partly together with water, offsetting the cooling effect at these parts, thus causing excessive heating and resultant damage to the pipes.

Therefore another, important point of the present invention lies in the development of walking beam equipment having a cooling water discharging device which eliminates air in these parts. As shown in FIG. 4, the cooling water discharging tubes 13 and 14 are inserted respectively into the supports 6 and 7, along their axes, so that the openings of said tubes are placed near the top of said supports. As mentioned above, cooling water is introduced through the water introducing valve 11, runs through the support 6, the horizontal member 8 and the support 7, and is discharged through the water discharging valve 12. In this case, air staying at A and B is constantly discharged through the cooling water discharging tubes 13 and 14, together with cooling water. As a result, the tops of the supports 6 and 7 are constantly cooled, thus preventing damage or melting due to heat.

Furthermore, this system of the present invention according to which the cooling water discharging tubes 13 and 14 are set along the direction of axes of the supports is excellent in cooling effect, as currents come into the discharging tubes 13 and 14 from all radial directions. Also, there is no danger of excessive heating, as the coolig water discharging tubes 13 and 14 are exposed directly in the furnace l.

As shown in FIGS. 1 and 2, the horizontal member 8 of this embodiment is a curved beam having a certain curve rate. This prevents the horizontal member 8 from contacting the supporting structure 3' of the fixed skid beam 2' during movement from (b) to (c), considering that said fixed skid beam 2 has been installed midway between the width of the movable skid beam 4, so as to transport to-be-heated materials of various sizes.

According to the present invention, however, there is no such limitation to the horizontal member 8. There is given in this specification only an embodiment of the case where horizontal members are used for the supporting structure for the movable skid beams, but similar system can be applied also for the fixed skid beams.

What we claim is:

l. A skid beam supporting structure for use in a heating furnace of the walking beam type having movable and fixed skid beams, said structure comprising a pair of vertically mounted tubular supports, said supports each being closed at the top and bottom ends thereof,

each of said supports having one of said movable skid beams attached at said top end thereof, a first of said supports having adjacent said bottom end thereof a cooling water supply opening, a second of said supports having adjacent said bottom end thereof a cooling water discharge opening; a tubular horizontal member fixed to said supports at positions downwardly spaced from said top ends thereof, said supports and said member forming an H shape structure; the interior of said member being in communication with the interiors of each of said supports; a cooling water discharging tube sheathed by and extending into each of said supports, the upper end of said tube being open and terminating adjacent said top end of said support; whereby water supplied from said cooling water supply opening is discharged through said upper ends of said water discharging tubes and said cooling water discharge opening.

2. A structure as claimed in claim 1, further comprising at least one fixed skid beam positioned between said movable skid beams.

3. A structure as claimed in claim 1, wherein said member is fixed to said supports at a position 30-40 percent of the height of said supports from said top ends thereof.

4. A structure as claimed in claim 1, wherein each of said cooling water discharging tubes is positioned along the axis of one of said supports.

mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,687,427 Dated August 29, 1972 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the heading of the printed specification after line 9 insert: Assignee--Nippon Steel Corporation Tokyo,Japan-.

Signed and sealed this 13th day of March 1973.

(SEAL) .Attest EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

1. A skid beam supporting structure for use in a heating furnace of the walking beam type having movable and fixed skid beams, said structure comprising a pair of vertically mounted tubular supports, said supports each being closed at the top and bottom ends thereof, each of said supports having one of said movable skid beams attached at said top end thereof, a first of said supports having adjacent said bottom end thereof a cooling water supply opening, a second of said supports having adjacent said bottom end thereof a cooling water discharge opening; a tubular horizontal member fixed to said supports at positions downwardly spaced from said top ends thereof, said supports and said member forming an ''''H'''' shape structure; the interior of said member being in communication with the interiors of each of said supports; a cooling water discharging tube sheathed by and extending into each of said supports, the upper end of said tube being open and terminating adjacent said top end of said support; whereby water supplied from said cooling water supply opening is discharged through said upper ends of said water discharging tubes and said cooling water dIscharge opening.
 2. A structure as claimed in claim 1, further comprising at least one fixed skid beam positioned between said movable skid beams.
 3. A structure as claimed in claim 1, wherein said member is fixed to said supports at a position 30- 40 percent of the height of said supports from said top ends thereof.
 4. A structure as claimed in claim 1, wherein each of said cooling water discharging tubes is positioned along the axis of one of said supports. 